Escort Vessel Automatically Rotative Winch System

ABSTRACT

The present invention discloses an escort vessel towline force responsive apparatus comprising a rotative winch system mounted to the deck of an escort vessel so that when the tow line between a distressed vessel and the winch system of an escort vessel angularly changes, the escort vessel winch system will automatically rotate until the line of force is substantially in linear alignment with the center line of the escort vessel winch system.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to winch systems and, more specifically, to a rotative winch mounted to the deck of an escort vessel so that when the line of force between a distressed vessel and the winch system of an escort vessel angularly changes, the escort vessel winch system will automatically rotate until the line of force is substantially in linear alignment with the center line of the escort vessel winch system.

2. Description of the Prior Art

There are other winch systems designed for escort tugs. While these systems may be suitable for the purposes for which they where designed, they would not be as suitable for the purposes of the present invention as heretofore described.

It is thus desirable to provide an escort tug with a deck mounted rotative winch so that when the winch rotates towards the line of force the heel angle of the tug decreases.

SUMMARY OF THE PRESENT INVENTION

A primary object of the present invention is to provide an automatically rotative winch system for an escort vessel tow line.

Another object of the present invention is to provide an escort vessel winch system that reduces the side force on the winch.

Yet another object of the present invention is to provide an escort vessel with a winch system that is deck mounted on a slewing ring.

Still yet another object of the present invention is to provide an escort vessel with a rotative winch system that is capable of reducing the heeling angle of an escort vessel without reducing the line pull.

Another object of the present invention is to provide an escort vessel with a rotative winch system that is capable of increasing line pull as the heeling angle of the escort vessel increases.

Additional objects of the present invention will appear as the description proceeds.

The present invention overcomes the shortcomings of the prior art by providing an automatically rotative winch mounted to the deck of an escort vessel so that when the tow line force between a distressed vessel and the winch system of an escort vessel angularly changes, the escort vessel winch system will automatically rotate until the line of force is substantially in linear alignment with the center line of the escort vessel winch system.

The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawings, which forms a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawings, like reference characters designate the same or similar parts throughout the several views.

The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

In order that the invention may be more fully understood, it will now be described, by way of example, with reference to the accompanying drawing in which:

FIG. 1 is an illustrative view of the present invention in use.

FIG. 2 is a side view of the present invention.

FIG. 3 is a side view of the present invention.

FIG. 4 is a view of method of the present invention.

FIG. 5 is a side view of the winch of the present invention.

FIG. 6 is a top view of the winch of the present invention.

FIG. 7 is a top view of the winch of the present invention.

FIG. 8 is a top view of the winch of the present invention.

FIG. 9 is a view of the winch anti-trip bearing of the present invention.

DESCRIPTION OF THE REFERENCED NUMERALS

Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, the Figures illustrate the method of constructing a catalog of the resources accessible through a network of the present invention. With regard to the reference numerals used, the following numbering is used throughout the various drawing figures.

-   -   10 force responsive towline apparatus of the Present Invention     -   12 winch     -   14 slewing ring     -   16 distressed vessel     -   18 escort vessel     -   20 line     -   22 propulsion force     -   24 center of pressure (COP)     -   26 beam     -   28 distance between propulsion unit and beam     -   30 distance between COP and beam     -   32 inner race     -   34 anti slip bearing

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following discussion describes in detail one embodiment of the invention. This discussion should not be construed, however, as limiting the invention to those particular embodiments, practitioners skilled in the art will recognize numerous other embodiments as well. For definition of the complete scope of the invention, the reader is directed to appended claims.

Referring to FIG. 1, shown is an illustrative view of the present invention in use. The winch system 10 of the present invention was designed for the purpose of increasing the line pull (steering force) and safety of tugs 18 escorting ships 16 in protective waters using a simple mechanical advantage. An escort tug 18 is defined as a tug tethered 20 to the stern of a large ship or tanker 16. In an emergency, if a tanker or ship 16 has a loss of power or rudder failure the escort tug 18 will be ordered to go to the port or starboard side of the tanker (line or hawser 20 is attached to the ship or tanker) and will be directed by the pilot to go into the indirect mode or power indirect mode. The indirect mode is defined as an escort tug at 45 degrees to the tanker and at a jackknifed position with the z drives (thrusters) facing towards the ship the forces of dragging the tug through the water will control or turn the ship or tanker. The indirect mode can be used and is effective at higher speeds but is harder to get into position.

The present invention 10 provides a winch system that turns toward the line of force the moment is decreased and the heel angle will be reduced for the same line pull.

Referring to FIG. 2, shown is a side view of the present invention. As shown in the illustration, for the tug 18 to be in equilibrium the equation P×X=COP×Y and P+T=COP (“P” is “Z” drive force 22, “T” is tow line force 26 and “COP” is the tugs center of pressure) 24 must be achieved. If you isolate the terms T=COP×(1−Y/X) is reduced the tow line 20 pull “T” will increase. As the winch of the present invention 10 rotates and “Y” becomes closer to the “COP” the ratio of “X” to “Y” 28, 30 is reduced and the line pull will increase with the same force at “P”.

Referring to FIG. 3, shown is a side view of the present invention. The winch system of the present invention 10 and staple 26 (tow point) rotates 32 on a large slewing ring 14 and reduces the side loading on the escort vessel 18 winch also producing a level toe line wind.

Referring to FIG. 4, shown is a view of the method of the present invention. As the winch system of the escort vessel 14 turns 26 toward the line of force 20 the moment is decreased and the heel angle of the escort vessel 14 is reduced for the same line pull. The winch rotates at a right angle to the tug, the line pull will remain the same with less of a heeling angle or as the heeling angle is increased the line pull will also increase.

Referring to FIG. 5, shown is a side view of the winch of the present invention. The winch system 12 and staple 26 (tow point) of the present invention 10 rotates via 32 on a large slewing ring 14 and reduces the side loading on the winch and also produces a level wind. As the winch system of the present invention turns toward the line of force the movement is decreased and the heel angle reduced for the same line pull. The winch rotates at a right angle to the tug, the line pull will remain the same with less of a heeling angle or as the heeling angle is increased the line pull will also increase.

Referring to FIG. 6, shown is a top view of the winch of the present invention. The winch system 12 and staple 26 (tow point) of the present invention rotates on a large slewing ring 14 and reduces the side loading on the winch producing a tow line level wind.

Referring to FIGS. 7 and 8, shown are top plan views of the winch system of the present invention 10. FIG. 7 illustrates the winch 12 and staple 26 in a forward position having inner race 32 and slewing ring 14 providing automatic rotation dependant on the line of force. The force responsive tow line apparatus 10 is mounted to travel at a right angle to the escort vessel deck thereby as the line of force between the escort vessel and distressed vessel angularly deviates from the center line of winch 12 and staple 26, winch system 10 automatically rotates until the line of force linearly aligns with the center line of winch system 10, as illustrated in FIG. 8.

Referring to FIG. 9, shown is a view of the winch anti-trip bearing of the present invention. Illustrated is inner race 32 and outer race 14 having anti-trip bearing 34 positioned thereon.

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of devices differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. 

1. A method of affecting line pull force between a distressed vessel and a powered escort vessel while simultaneously affecting the heeling angle of the escort vessel comprising: a) securing a line between the distressed vessel and an escort vessel winch; b) mounting the escort vessel winch on a slewing ring; and c) automatically rotating the escort vessel winch in the direction of the line pull force.
 2. The method of claim 1 whereby the heeling angle of the powered escort vessel is decreased for the same line pull force by rotating the escort vessel winch toward the escort vessel center of pressure.
 3. The method of claim 2 whereby the line pull force is increased as the heeling angle of the powered escort vessel is increased.
 4. Apparatus for affecting line pull force between a distressed vessel and a powered escort vessel while simultaneously affecting the heeling angle of the escort vessel comprising: a) a line secured between the distressed vessel and an escort vessel winch; b) an escort vessel having a winch mounted on a slewing ring; and c) means for automatically rotating the escort vessel winch in the direction of the line pull force.
 5. The apparatus of claim 4 wherein the heeling angle of the powered escort vessel can be decreased for the same line pull force by rotating the powered escort vessel winch toward the escort vessel center of pressure.
 6. The apparatus of claim 5 wherein the line pull force can be increased by rotating the powered escort vessel winch toward the escort vessel center of pressure and increasing the heeling angle of the powered escort vessel.
 7. The apparatus of claim 6, further comprising an anti-slip bearing positioned between the inner race and the slewing ring.
 8. The apparatus of claim 7, further providing a safety mechanism for an escort vessel wherein an automatically rotative winch will reduce the potential for capsizing an escort vessel by moving the staple closer to the escort vessel center of pressure. 